Effect of maternal nicotine exposure on neonatal rat lung development: protective effect of maternal ascorbic acid supplementation.

In previous studies it was shown that maternal nicotine exposure during pregnancy and lactation interfered with fetal and neonatal lung growth and development. It was suggested that the adverse effects of maternal nicotine exposure on the lungs of the offspring may be due to inadequate protection of these lungs against oxidants. Wistar rats were used in this study. After mating the rats were randomly assigned into 4 groups, namely a control group, a group receiving only nicotine, a group exposed to only vitamin C, and a group exposed to both nicotine and vitamin C. The aim of this study was, firstly, to determine the effect of maternal nicotine exposure (1 mg/kg body weight/day, subcutaneously) during gestation and lactation on the lungs of the offspring; secondly, to test whether the subcutaneous administration of vitamin C (0.5 mg/kg body weight/day) influences lung development; and, lastly, to determine whether subcutaneous administration of vitamin C will prevent the adverse effects of maternal nicotine exposure on lung development in the offspring. Morphologic and morphometric techniques were used to determine the effect of nicotine and vitamin C on lung development in the offspring on postnatal days 14, 21, and 42. The results showed that maternal exposure to nicotine only or vitamin C only resulted in a gradual deterioration of the parenchyma of the lungs of the offspring. These changes, which resembled microscopic emphysema, only became evident after the lungs of the offspring reached maturation. Those animals that were exposed to both nicotine and vitamin C via the placenta and mother's milk were less severely affected. It is also not advisable to use subcutaneous administration of vitamin C during gestation and lactation to prevent smoke- and nicotine-related effects on the developing lung, and other strategies should be investigated.